Scholarly article on topic 'Harmonizing the quantification of CCS GHG emission reductions through oil and natural gas industry project guidelines'

Harmonizing the quantification of CCS GHG emission reductions through oil and natural gas industry project guidelines Academic research paper on "Environmental engineering"

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Abstract of research paper on Environmental engineering, author of scientific article — Karin Ritter, Robert Siveter, Miriam Lev-On, Theresa Shires, Haroon Kheshgi

Abstract The technological option of capturing CO 2 from large point sources, compressing, transporting, and injecting it for long -term storage holds the potential for playing a key role in reducing greenhouse gas (GHG) emissions while providing affordable energy. The oil and natur al gas industry experience and expertise provide confidence in carbon capture and geological storage (CCS) as an effective GHG emission mitigation option. However, companies need consistent, reliable, and credible methodologies to derive GHG emission and emission reduction estimates. Harmonizing the quantification of GHG emission reductions, by applying common principles and criteria, supports efficient and consistent development of additional project activities. This paper provides an overview of the P etroleum Industry Guidelines for Greenhouse Gas Emission Reduction Projects (referred to as the Project Guidelines), a collaborative effort between the American Petroleum Institute (API) and the International Petroleum Industry Environmental Conservation Association (IPIECA) to develop guidelines for accounting and reporting of GHG emission reduction projects of interest to the oil and natural gas industry. Key concepts from the Project Guidelines for evaluating, quantifying, documenting, and reporting GHG emission reductions are presented with a specific focus on CCS activities. The paper draws from the Project Guidelines in add ressing the selection of appropriate baseline candidates, boundaries for scenario assessment, and compatible monitoring considerations. Case studies are used to demonstrate the application of commonly accepted emission reduction principles for CCS projects. Through the Project Guidelines, API and IPIECA aim to assist the petroleum industry in identifying, assessing, and developi ng CCS projects. By working toward consistent standards for GHG emissions reductions, our industry demonstrates its commitments toward environmental improvements and p romotes the development of real and sustainable actions to reduce GHG emissions.

Academic research paper on topic "Harmonizing the quantification of CCS GHG emission reductions through oil and natural gas industry project guidelines"

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Energy Procedia 1 (2009) 4451-4458 ^^^^^^^^^^

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GHGT-9

Harmonizing the Quantification of CCS GHG Emission Reductions Through Oil and Natural Gas Industry Project Guidelines

Karin Rittera*, Robert Siveterb, Miriam Lev-Qnc, Theresa Shiresd, Haroon Kheshgi6

a American Petroleum Institute (API), ¡220 L Street, N.W., Washington, D.C., USA 20005 hInternational Petroleum Industry Environmental Conservation Association (IPIECA), 209-215 Blackfriars Road, London, United Kingdom, SEI

° The LEVON Group, 236 Marjorie Avenue, Thousand Oaks, CA, USA 91320 d URS Corporation, 9400 Amberglen Blvd., Austin, TX, USA 78729 'ExxonMobil Research & Engineering Company, 1545 Route 22 East, Annandale, NJ USA 08801 -3059

Abstract

The technological option of capturing C02 from large point sources, compressing, transporting, and injecting it for long-term storage holds the potential for playing a key role in reducing greenhouse gas (GHG) emissions while providing affordable energy. The oil and natural gas industry experience and expertise provide confidence in carbon capture and geological storage (CCS) as an effective GHG emission mitigation option. However, companies need consistent, reliable, and credible methodologies to derive GHG emission and emission reduction estimates. Harmonizing the quantification of GHG emission reductions, by applying common principles and criteria, supports efficient and consistent development of additional project activities.

This paper provides an overview of the P etroleum Industry Guidelines for Greenhouse Gas Emission Reduction Projects (referred to as the Project Guidelines), a collaborative effort between the American Petroleum Institute (API) and the International Petroleum Industry Environmental Conservation Association (IPIECA) to develop guidelines for accounting and reporting of GHG emission reduction projects of interest to the oil and natural gas industry. Key concepts from the Project Guidelines for evaluating, quantifying, documenting, and reporting GHG emission reductions are presented with a specific focus on CCS activities. The paper draws from the Project Guidelines in add ressing the selection of appropriate baseline candidates, boundaries for scenario assessment, and compatible monitoring considerations. Case studies are used to demonstrate the application of commonly accepted emission reduction principles for CCS projects.

Through the Project Guidelines, API and IPIECA aim to assist the petroleum industry in identifying, assessing, and developi ng CCS projects. By working toward consistent standards for GHG emissions reductions, our industry demonstrates its commitments toward environmental improvements and p romotes the development of real and sustainable actions to reduce GHG emissions.

© 2009 Elsevier Ltd. All rights reserved.

* Corresponding author. Tel.: +1 -202-682-8472; fax: +1 -202-682-8031. E-mail address: Ritterk@api.org.

doi:10.1016/j.egypro.2009.02.261

Keywords: carbon capture and storage; greenhouse gas emissions; GHG emission reductions; guidelines; petroleum indiustry

1. Introduction

Carbon capture and storage (CCS) refers to the chain of processes to collect or capture a C02 gas stream, transport the C02 to a storage location and inject the C02 into a geological formation for long -term isolation from the atmosphere. Application of CCS toward climate change mitigation builds on existing industrial operations, for example in the separation of C02 from gas mixtures, in the compression, transport, and injection of C02, and in corrosion control, and may be compatible with many current energy infrastructures. Many of the methods and techniques to identify appropriate sites, to conduct injection operations, to project subsurface performance, to manage injected gases and substances, and to avoid or mitigate unwanted developments are well known to the oil and natural gas industry.

Governmental and private organizations are evaluating options for reducing greenhouse gas (GHG) emissions, developing project plans, and implementing emission reduction projects. While the overarching goal of reducing GHG emissions is consistent among these initiativ es, there is a need for sound technical overarching guidance that is suitable for a broad range of climate change regimes or GHG registries and will serve the oil and natural gas industry's global operations.

To meet this need, the American Petroleum Institute (API) and the International Petroleum Industry Environmental Conservation Association (IPIECA) have published guidelines for greenhouse gas (GHG) emission reduction projects relevant to the oil and natural gas industry [1]. These Project Guidelines explain key concepts for GHG reduction project accounting and provide principles and criteria for credible GHG emission reduction quantification. A second part of the Project Guidelines specifically addresses CCS projects [2]. These initiatives build on earlier protocol development work contained in the Petroleum Industry Guidelines for Reporting Greenhouse Gas Emissions [3] and the API Compendium of Emissions Estimating Methodologies for the Oil and Gaslndustry [4].

As summarized here, the IPIECA/API guidelines for CCS projects apply a step -wise approach for assessing and quantifying potential GHG reductions for CCS applic ations of interest to the oil and natural gas industry. Appropriate site selection, operation, and monitoring are all recognized as important elements for CCS to be a safe and secure GHG emission reduction option. Considerations for assessing baseline candidates, estimating emissions for particular baseline or project emission sources, and risk-based monitoring are presented through the ecampl es provided.

2. Application of emission reductions guidelines

Figure 1 presents the primary steps for quantifying emission reductions. Each of these steps are described further and illustrated through the examination of two example CCS projects.

2.1. Defining theproject

The first step, defining the project, provides a written description of the emission reduction activity. A GHG reduction project is a recognizable and distinct activity or set of activities that reduce global GHG emissions, increase the storage of carbon, or enhance GHG removals from the atmosphere. CCS as a GHG reduction project activity avoids C02 emissions to the atmosphere by injecting the C02 and ultimately storing it in a geological formation. For a CCS project to be regarded as a climate change mitigation activity, the geological formation at the selected site must have appropriate long-term containment capability.

Figure 1. Steps for quantifying emission reductions

t 1 Stepl: Define Project ❖ Describe the activity or set of activities that reduce GHG emissions

> > Step2: Determine Baseline Scenario ❖ Identify baseline candidates for each project activity ❖ Determine the baseline scenario based on sound, technical considerations and guided by common practice ❖ Examine the geographic area and time frame for which the baseline is applicable

Step3: Determine Assessment Boundary

Identify potential sources, sinks, or reservoirs controlled by, related to, affected by, and relevant to the baseline scenario

Step4: Quantify Emission Reductions

Quantify GHG emissions for the project activity

Estimate GHG emissions associated with the baseline scenario

Quantify the emission reductions

Emission Reductions = Baseline emissions

2.2. Determining the baseline scenario

Projectemissions

GHG reductions must be quantified relative to a reference level of GHG emissions, referred to as the baseline scenario. Because the baseline scenario is a hypothetical situation, there may be multiple candidate scenarios for what might have happened in the absence of the project. Potential candidates represent situations or conditions that plausibly would have occurred in the absence of the reduction project. Determining the baselines scenario from among these candidates is a complex task, which may involve subjective and obj ective elements. In general, determination of the baseline scenario should be based on a sound, technical basis, guided by commonly accepted practice. Common practice provides the most objective means of identifying what would have happened in the absence of the project.

2.3. Determining the assessment boundary

After defining the project and determining the baseline scenario, the next step is to determine the assessment boundary. The assessment boundary encompasses GHG emission sources, sinks, and reservoi rs controlled by the entity implementing the project, related to the GHG reduction project, affected by the GHG reduction project, and relevant to the selected baseline scenario.

2.4. Quantifying emissions

Greenhouse gas emission reductions are quantified as the difference between the baseline emissions and the reduction project emissions, where baseline emissions are determined for the same quantity of output as the project. Baseline emissions are emissions that would have occurred from a referenced operation (baseline scenario) without carbon capture but with the same output as the project activity (e.g., the volume of natural gas processed for a gas processing facility). Because the baseline emissions are representative of a hypothetical scenario, baseline emissions are only estimates. Baseline emissions should reflect emission sources associated with each step of the CCS chain, but that would have occurred in the absence of the project.

Although baseline and project emissions associated with CCS will primarily focus on sources of C02 (including C02 captured as part of the project or C02 emissions resulting from energy requirements to capture, transport and inject C02), methane (CH4) and nitrous oxide (N20) emissions sources should also be assessed. Both baseline and

project emissions can be expressed by the following general equation. The equation terms are defined further in Table 2.

Emissions = VENT + CMB + FUG + IND (Equation 1)

Table 1. Terminology associated with emission qu antification equation.

Equation Term Baseline Terminology Project Terminology

VENT Vented CO 2 emissions from baseline operations or equipment that would have occurred in the baseline scenario. (For most petroleum industry CCS projects, the volume of CO 2 captured by the project would be included in this amount.) Vented emissions associated with the project include pipeline vents during normal operations and maintenance/upset conditions and compressor blowdown emissions from transporting the C02 to the injection site.

CMB Direct combustion emissions that would have occurred in the baseline scenario. These might include fuel consumed in stationary combustion equipment or emissions from flares or acid gas incineration. Combustion emissions from fuel consumption associated with compressing the captured gas stream, transporting the gas to the storage reservoir and injecting the gas into the reservoir.

FUG Fugitive CO 2 emissions from baseline equipment that would have occurred in the baseline scenario. Fugitive emissions associated with pressurized equipment used to capture, transport and inject the gas stream.

IND Indirect emissions that would have occurred from electricity purchased from outside sources in the baseline scenario. Indirect emissions from elec tricity used to operate capture, transport, and storage equipment

3. Case study for CCS associated with acid gas removal

The first case study examined here is based on a project designed to recover C02 emitted from gas treatment operations associated with a newly constructed liquefied natural gas (LNG) facility and inject it into a deep saline formation. Table 1 outlines the operating parameters associated with this example. A schematic diagram of the project activity is shown in Figure 2.

Table 2. Operating parameters for case study #1

Parameters for C02 Capture, Transport and Injection in a Saline Formation

20.8xl06 Sm3/day (734 xlO6 scf/day) of natural gas is produced from 9 offshore wells and is piped to an onshore LNG facility. The produced natural gas contains 3.9 to 5.4 mol% CO 2, 0-2mol% H 2S, and 81-83 mol% CH 4. (The remaining gas constituents are inconsequential to this example.)

Energy required for the baseline scenario is estimated to be 1.87 x 10 J (1772 MMBtu) of natural gas and 136.8 x 1012 J(38,000MW-hr)of electricity

C02 is separated from the natural gas using an amine unit and amine regeneration prior to cooling the produced gas to form LNG containing 99% CH4.

Captured CO 2 is compressed using multiple engine-driven compressors and electric -driven pumps to transport the CO 2 stream 152 km (94 miles) to an offshore CO 2 injection well and inject the C02 into the deep saline formation. Facility fuel and electricity usage records, and CO 2 metering records indicate th at, on an annual basis, 35.9 xl06Sm3(1.27 xlO9 set) of fuel gas and 1.27 xlO13 J(3,528MW-hr) of electricity are consumed at the compression/pump and metering facilities to compress 700 x 103 tonnes C02 per year that is captured from the LNG plant. TheCO 2 is injected into a deep saline formation, separated from the ocean floor by a gas bearing forma tion, an oil bearing formation, and a thick shale formation. The properties of the reservoir make storage of the CO 2 a viable, long -term option and minimize the potential for an accidental release as a result of natural occurrences

Through an analysis of the potential candidates for this case study, the further processing of the acid gas stream in a sulfur plant is determined to be the most probable baseline s cenario. It should be noted that this case study is presented for illustrative purposes only. Actual project activities will require an assessment of candidates and characteristics specific to the project application. Regulatory or voluntary GHG regimes may require additional details and justification for baseline scenario determination.

Produced LNG

LNG Plant r 1 1 1

J Purified Natural Gas k r- -.

■ GasTreatment . Operations ■ ■

W Produced

Capture

Legend

Project emissions

Process additions resulting from

the project

GHGemissions dueto energy consumption

G02 Process Vents & Fugitive . Emissions

Captured CO

........J?.......^.....\

pump meter -

C02 compression and dehydration

C02 Process Vents & Fugitive

CO 2 Process Vents & Fugitive Emissions w

■8 o a

Pipeline transport

Assessment Boundary

Storage

Figure 2. Project illustration of C02 capture, transport and injection in a saline formation

In this example, the gas treatment and LNG operations are similar in bo th the baseline and project scenarios, and remain unaffected by the project. As a result, the assessment boundary for the baseline scenario includes only the C02 that would have been released to the atmosphere. All estimation methods used for this example are based on those compiled in the API Compendium [4]. Additional details are provided in the CCS Guidelines document [2]. Results for this case study are shown in Table 3.

Table 3. Estimated emission reductions for case study #1: CCS into a deep sali neformation

Baseline Scenario Tonnes CO 2 Eq. Project Tonnes CO 2 Eq.

Vented Emissions (VENT) 700,000 246

Direct Combustion Emissions (CMB) 0 86,187

Fugitive Emission (FUG) 0 425

Indirect (Electricity) Emissions (IND) 0 3,095

Total Emissions 700,000 89,953

Annual Net GHG Reductions 610,047

4. Case study for CCS associated with enhanced oil recovery

A second example is provided to illustrate the application of the emission reduction guidelines for a CCS project where the captured C02 stream is used for enhanced oil recovery (EOR). For this case study, C02 is recovered from a natural gas processing facility, transported by pipeline, and injected into an oil production field for EOR. It is

assumed for this example that the entity conducting the project is a Joint Venture Partner in the EOR operations, but does not own or operate the gas processing facility or the C02 transport operations. Operating parameters and assumptions associated with this example are summariz ed in Table 4. Figure 3 illustrates the project activity and assessment boundary.

Table 4. Operating parameters and assumptions for case study #2

Parameters and Assumptions for C02 Capture, Transport and Injection for Enhanced Oil Recovery

TheCO 2 stream separated from the natural gas and hy drogen sulfide (H 2S) is captured and routed to compression/dehydration units. These activities and the increased energy requirements associated with them are shown within the assessment boundary, but may physically be located within the gas processing fac ility.

Composition of the captured gas is 98.4 percent CO 2, and 1.6 percent methane (CH 4) by volume.

The recovered CO 2 is compressed using multiple engine -driven compressors and electric -driven pumps to transport the CO 2 stream 32 km (20 miles) to the oi 1 production field and inject it into the reservoir for EOR.

Facility fuel and electricity usage records, and CO 2 metering records indicate that, on an annual basis, 31.7 xl06m3 (1.12xl09 scf) of fuel gas and 17.35x1012 J(4.82 GW-hr) of electricity are consumed at the compression/pump and metering facilities to compress 510 xlO m (18 Bscf)CO 2 that is captured from the gas plant.

Crude and associated gas produced from the EOR operations are sent to a central processing facility. C02 contained in the associated gas is separated through an amine unit, compressed, and re -injected into the EOR process, thereby recycling the CO 2 back into the reservoir.

The captured, anthropogenic CO 2 from the gas processing facility replaces underground -sourced CO 2 used fo r tertiary oil recovery.

The disposition of the hydrogen sulfide in the produced natural gas is unchanged between the project and the baseline scenario.

The injection of CO 2 for EOR is planned for the foreseeable future of the reservoir.

Common practice in the area is to purchase the underground -sourced CO 2 for EOR operations.

For the gas processing facility, venting the exhaust from the amine unit is common practice, as allowed under the terms of existing regulations in the facility location.

Common practice for the EOR operation is to capture and recycle the C02 produced from the EOR production wells.

Recovered Produced

Figure 3. Project illustration of C02 capture, transport and injection for enhanced oil recovery operations

For this example, there are three important aspects to consider for the baseline scenario and the assessment boundary:

1. The disposition ofthe C02 associated with the gas processing facility;

2. The source ofthe C02 used for EOR; and

3. The disposition ofthe C02 produced from the EOR production wells in the C02-floodedfield. Assumptions associated with these aspects are noted in Table 4 for this case study and may not be applicable to

actual project activities. The CCS Project Guidelines document [2] provides additional details on the screening procedures applied in assessing the baseline candidates.

The emission reductions results for this case study are shown in Table 5. All calculations are based on methodologies present ed in the APICompendium [4].

Table 5. Estimated emission reductions for case study #2: CCS for EOR

Baseline Scenario Tonnes CO 2 Eq. Project Tonnes CO 2 Eq.

Vented Emissions (VENT) 1,048,149 51

Direct Combustion Emissions (CMB) 0 76,118

Fugitive Emission (FUG) 298 143

Indirect (Electricity) Emissions (IND) 12,675 4,227

Total Emissions 1,061,122 80,539

Annual Net GHG Reductions 980,583

5. Monitoring considerations

CCS may play a significant role in mitigating GHG emissions. However, much of this depends on public and policy maker acceptance, which necessitate demonstrating that potential local risks or other concerns associated with long-term CO 2 storage are managed.

Monitoring for CCS has two purposes. The first is from a GHG emissions point of view, to establish the amount of avoided GHG emissions (net emission reduction). Here, monitoring refers to the continuous or periodic assessment of GHG emissions and removals with the purpose of determining emissions and emission reductions from the project. Monitoring must be sufficient to allow the transparent quantification of GHG reductions. Methodologies for monitoring can be direct or indirect and include estimation, modeling, measurements, and/or calculation approaches.

The second purpose is for risk assessment, avoidance, and mitigation. In terms of geological storage ofC02, monitoring includes the methods to assess that the C02 in the subsurface is behaving as predicted and according to any permit requirements or regulations. Subsurface monitoring is used to determine that the risk of emissions to the environment is not increasing above accepted levels, usually established by the permit for the storage project. Additionally, monitoring should establish that C02 does not leak into (and contaminate) other energy and mineral resources in the subsurface, shallow potable groundwater, and soils.

For CCS operations, monitoring is an iterative, risk -based process, utilizing information from ongoing assessments of characteristics that are specific to a particular CCS project. As a result, monitoring plans should be developed on a case-by-case basis to manage potential risks for the specific CCS application. A risk-based monitoring approach applies risk assessment techniques to identify key risks of physical leakage for the specific project, then appropriate monitoring techniques are identified to manage the risks and performance is demonstrated against the monitoring plan. Monitoring practices are expected to continue to evolve with improved technologies, new information, and ongoing risk management.

6. Conclusions

Technologies for the capture of C02 from fossil fuel use and long-term storage underground offer significant potential for meeting society's energy needs while mitigating GHG emissions. An established history of CCS activities and broad expertise in its application by oil and natural gas industry provide a basis for confidence in the use of CCS as a GHG emission reduction option. Further demonstrations will continue to expand this experience, highlight best practices, increase alignment among experts, and assist in building broad understanding and public acceptance.

The IPIECA and API guidelines for GHG emission reduction projects [1], and specifically the guidelines for CCS as an emission reduction option [2], support the consistent evaluation, quantification, documentation and reporting of GHG emission reduction activities. This activity is one of a diverse set of initiatives aimed at improving the understanding of CCS and gaining experience in its application for safe and secure GHG emission reductions.

Ackn owledgements

Much of the material in these guidelines builds on the Intergovernmental Panel on Climate Change Special Report on Carbon Capture and Storage [5], as well as ongoing research, developments and CCS demonstrations by the U.S. Department ofEnerg y and the International Energy Agency.

The authors wish to acknowledge the support and contributions of the API and IPIECA member companies in the developmentof the Oil and Natural Gas Industry Guidelines for Greenhouse Gas Reductions [1] and the follow -on report Part II: Carbon Capture and Geological Storage Emission Reduction Project Family [2].

References

1. International Petroleum Industry Environmental Conservation Association (IPIECA) and America n Petroleum Institute (API), Oil and Natural

Gas Indus try Guidelines for Greenhouse Gas Reduction Projects, London, United Kingdom and Washington DC, 2007.

2. International Petroleum Industry Environmental Conservation Association (IPIECA) and American Petroleum Institute (API), Part II: Carbon

Capture and G eological Storage Emission Reduction Family, London, United Kingdom and Washington DC, 2007

3. International Petroleum Industry Environmental Conservation Association (IPIECA), American Petroleum Institute (API), and International

Association of Oil and Ga s Producers (OGP). Petroleum Industry Guidelines for Reporting Greenhouse Gas Emissions, London, United Kingdom and Washington DC, 2003.

4. API, 2004. Compendium of Greenhouse Gas Emissions Methodologies for the Oil and Gas Industry, American Petroleum Institute,

Washington, DC, 2004; amended 2005.

5. Metz, B., O. Davidson, H. C. de Coninck, M. Loos, and L. A. Meyer (eds.) Intergovernmental Panel on Climate Change (IPCC) Special Report

on Carbon Dioxide Capture and Storage. Cambridge, United Kingdom and New York, NY 2005.